This prospective cohort study has been performed to evaluate the changes in student nurses smoking habits and beliefs during their training. The source of information was an anonymous questionnaire about tobacco smoking, administered to students who entered the first year of School of Nursing in Florence in 1991-1992, 1992-1993 and 1993-1994. Five hundred and thirty-six (95%) of these student nurses completed the questionnaire. Five hundred and one (93%) of these 536 respondents completed the questionnaire again at the end of the third (final) year of training. Student nurses who smoked increased the average number of cigarettes smoked per day (p < 0.01) and the degree of dependence to nicotine (p < 0.01). Tobacco smoking remained widespread and the percentage of ex-smokers who started smoking again increased (p < 0.05). The knowledge about the health hazards due to tobacco smoking remained generic and the prevalence of current smokers among student nurses and health care workers was overestimated. We conclude that Nursing School does not succeed in reducing the smoking habits of students. Effective antitobacco strategies and smoking cessation services still need be organized in Italy.